Project 99% complete.

[dwightp]

Several years in the works, finally see the light at the end of the tunnel. Thanks to all those that helped!!!

Enjoy. I certainly am!







This...


or this...

[MuffinMan]

I love it!

(the steering wheel is a bit small, though, eh?)

[Oh Haha]

Sweet!!

[Beethoven]

Mein Gott, what are those gauges in the middle console for??

[911gilley]

Looks awesome!
I know what you mean about seeing light at the end of the tunnel. I'm nearing completion of my project car (complete ground-up restoration) and am beginning to see a slight hazy dim glow at this stage).

What year is it (84?) and how do you like the carbs vs FI?

[dwightp]

"(the steering wheel is a bit small, though, eh?)"

Steering wheel?.....dooooohhh
No wonder it was soooo hard to turn. lol!

This better?

"Mein Gott, what are those gauges in the middle console for??"

The gauges are the clocks for 6 different time zones.
Actually, they are cht gauges.

"What year is it (84?) and how do you like the carbs vs FI?"
79
TWM 3006 Throttle Bodies...bear to setup. But when they are, wow!

Good luck on your project. Post some pic's.

[Yellowbird RS]

Nice!!!
Love it!

[temo79]

"79"

not in california I see.
good job though!!!

[temo79]

what's 1% left ?

[Chuck Moreland]

Dwight, very nice. What EMS are you using? I'm getting ready to put TWMs and EFI on my car.

What about the TWMs did you find difficult?

[dwightp]

"what's 1% left ?"
Oh, is a project ever 100% complete? I've got constant MAP trimming and tweeking going on all the time.

"What EMS are you using?"
Motec M48

"What about the TWMs did you find difficult?"
Don't get me wrong, these are nice TB's. The 3006 series doesn't have the common shaft like the 3003 series. Linkage set-up is a little more involved. Running alpha-n. Idle has been a challenge for several reasons. Linkage, size of the tb's, injector set-up, etc. Been a huge learning experience.

Chuck:
You are one of the vendors I owe a thanx to. I have several of your suspension and oil parts on the project. Solved many problems and potential problems with high displacement upgrade. Salute.

[Bill Verburg]

very, very nice!

[84porsche]

Very beautiful - what is the keypad for?? I doubt its for a phone.

[CBRacerX]

TWM makes nice stuf alright! I also used the ITG filters that you have. One word of caution on them - they are not fireproof. Ask me how I know

Just be sure the engine doesn't have a tendency to cough back thru the throttle bodies (like a certain RSR cam and Weber combination that I built).

Enjoy!!!!!

Chris

[dwightp]

"what is the keypad for?? "

ign/starter cutout. To play, you need to know the code. Another nice thing is having a wheel speed sensor input to the motec. Simple setting on the computer. Keeps those valets and shops to less than x mph/y RPM before the fuel/ign cut.

[Porschekid962]

Very nice engine. My dad and I are beginning our EFI engine soon after the 930 brakes go on. God I cant wait to start dialing in the M48 or DTA, havent decided yet.

Did you consider DTA at all? I know Motec is king and all but for a street car seems a bit too pricey and the DTA is very nice. Like they say, you've got to pay to play.

[kach22i]

Be sure to inform your insurance company to increase your replacement cost. I just had Hagerty Insurance increase my value up 4,000 for an extra $30 a year.

I'd hate to see one of those trees resting on that beauty.

[beepbeep]

Originally posted by dwightp
Don't get me wrong, these are nice TB's. The 3006 series doesn't have the common shaft like the 3003 series. Linkage set-up is a little more involved. Running alpha-n. Idle has been a challenge for several reasons. Linkage, size of the tb's, injector set-up, etc. Been a huge learning experience.

[/B]

Ahh, the joys of making engine idle with TWB's and Alpha-N

Most of the times it's quite hard for multiple reasons. First of all, it's hard to mechanically synchronize all those flappers to flow exactly the same amount of air, so one cylinder always gets more air then the other.

There is a trick to even them out:

Take a small rubber hose from each runner and connect it to central miniature plenum in the middle. Those runners that draw more air will send some of it to those that don't, leveling it out. At bigger throttle openings those hoses won't matter as they are too thin.

If you still have problems I suggest increasing hose-diameter and connecting MAP-sensor to central "plenum", and running in mixed mode (MAP on idle and low-RPM, going for Alpha-N at higher loads).

Alpha-N makes for great engine responce on track-car but is somewhat hard to get civilized :-)

Please post your expiriences, I'm eager to hear! There are not many running Alpha-N on their 911 engines.

[dwightp]

"Did you consider DTA at all?"
Oh yes, and several others. DTA has some nice units as do many other vendors. To be truthful, I went with Motec as it was being used by the engine builder I was working with. We were going to dyno tune togther, showing me the ropes. I was also too buried on research for the mechanical side of the engine (designing for my desired curve characteristics) to do much ECU research. After the fact, there are many nice units! Hard to go wrong. I did look at one that was sooo flexible (and complicated). Too many states and variables for someone at my level to master in a short amount of time. There is something to be said for simplicity.

One thing I found kinda of nice, is that you can download some executable on your pc for many of these ecu's. Run them, navigate, change values. Might give you an idea what you are getting into on the tuning side.

Insurance:

Great idea. I'll look into that soon.

Beep-Beep (Alpha-N tuning):
Man o' man. I've got sooo much to say here. I'll save it for a little later. Maybe another thread. The throttle response is sooooo nice.

[dwightp]

"Take a small rubber hose from each runner and connect it to central miniature plenum in the middle. Those runners that draw more air will send some of it to those that don't, leveling it out. At bigger throttle openings those hoses won't matter as they are too thin."

Ya know, after trial and trial with the TB's, I was able to get it to idle at about 11k. This was without ever touching the bypass screws. They remained in from the dyno tuning work. The only problem I had left was TB cross linkage to engine bellcrank. Kinematics are not quite right for just off of idle. I'm working that issue too. Other than the linkage problem and lack of brake boost, it was driveable. Switched back to 3.2 type intake (still aplha-n program) and determined that I was having some dead time problems with the injectors. Evident around idle. Addressed that and can now get a repeatable, stable idle at around 10k.

Since the 1st TB trials, I have made a vacuum distributor for the TB's. Primarily to get some vacuum assist back with the TB's. I'll also be utilizing the bypass screws. However, if what you recommend is true, I might get the additional benefit of easier idle tuning. I was going to install a small vacuum check valve in each cylinder's line, but now, I'll probably play with it both ways to try your suggestion. I'm not sure I want to make the jump to a map to alpha-n transition method just yet. I believe I can go alpha-n all the way and use ambient pressure for fuel trim.

I've got the big dia's TBs too. That doesn't help, I know.

Winter project is to make fuel system capable for E85 for next spring. It's readily available in the area and easily set-up with the Motec. I could use the extra octane margin due to a higher than usual CR. I've been running 101 for the last several months, It's readily available too at a local speed shop but a bit pricey. About $3.50/gal. I know, price is relative. Nice thing about living in a historical oil town with refineries close.

I'll post more as it developes.

Okay, okay. Maybe not 99% complete now. I just lowered the % a bit.